It is best to set your catch-all to :fail:. See http://www.configserver.com/free/fail.html for an explanation of the reasons that you should. If the account doesn’t exist you run the risk of e-mail not being accepted (sender verify checks will fail). Unfortunately, you cannot create a forwarder to /dev/null straight through cPanel. If you try to create a forwarder for no-eply@yourdomain.com => /dev/null, cPanel will append @domain.com to /dev/null. So you should contact your hosting provider and ask them to create the forwarder manually for you.

But there is one problem again. It is advised not set a forwarder to :fail: as sender verify checks will fail. Go into cPanel and setup a forwarder to :blackhole:

This way sender verify checks will work and [highlight]email for that address will be deleted[/highlight]. There is not even anything needed to contact your hosting provider you can do it within cPanel yourself (if at all you have the access of CPanel).

Some smart people ask me:

If we setup like a regular email account and put the quota at zero, it should work very well. It is so simple…!

But there are chances that the sent emails to this address will be sitting in the queue, one good thing about this approach is that if anyone does send an email to a no-reply address they will eventually get a MAILER DEMON saying that the email was not received (as mailbox was full)…!!!

How funny it would be…!

There are sound technical reasons that you should only use :fail: and not :blackhole: on a cPanel server running exim. We have conducted quite extensive testing to establish this configuration is best and outline the reasons here. In general the two different settings both discard email not destined for a POP3 account, an alias or a catchall alias. However, ever since cPanel included theverify = recipient code in the standard cPanel ACL section for exim, the way email is discarded differs with the two methods quite starkly. Read more…